Return bend



oct. 1 2, 1937.

5 Sheets-Sheet 1 F. E. KEY

RETURN BEND Filed March 8, 1935 /4/ 1 f uw F. E. KEY

RETURN BEND Oct. 12, 1937.

Filed March 8, 1955 3 Sheets-Sheet 2 lill l Oct. 12, 1937. y F. E, KEY 2,095,445

RETURN BEND Filed March s, 1935 s sheets-sheet. :s A

bgg 5 Mae/7727) n Freien/6W5. @y

` Patented Oct. ,12, 1937 UNITED STATES i PATENT oFFlc-E RETURN BEND Application 'Mn-cn s, 193s,- serisi No. 9,926

Claims.

This invention relates to return bends forming connections between the ends of tubes in oil stills which are subjected to high temperatures and high pressures.

Inone aspect, the present invention comprises certain additions and improvements inthe type of return bends disclosed in my prior Patent No.

i '1,987,300, January 8, 1935, and an object of the invention is to provide improvedI means fo connecting the housing sections to permit relative longitudinal adjustment thereof and, at the same time, maintaining leak-proof joints between the ends of the return bend and the housing sections. The improved connection .between the housing sections permits certain limited lateral and longi- `tudinal adjustments of said sections as required to maintain leak-proof joints with the return bend and said connection also prevents the housing sections from twisting .or turning relatively.

Another object of the invention is to provide improved means for holding the housing sections in proper connection with the tubes. Another object of the invention is to provide a return bend embodying novel features whereby 25' the return bend may be conveniently detached or pulled from the housing sections. Other objects of the invention will be apparent fromthe following description, reference being made to the annexed drawings, in which- Fig. 1 is an end elevation of a pre'erred form of the invention. 'l

"Fig, 2 is a cross sectional View on the line 2 2 of Fig. 3.

Fig. 3 is a sectional view of the return bend and g5 housing s'ectionsmounted in connection with the ends of tubes. t

' Fig. 4 is a vi'ew approximately-on theA line 4-4 of Fig. 3.

Fig. 5 is a relatively enlarged view, partly in 40 section, showing alternative means for holding .the housing sections in connection with the tubes.

Fig..6 is a similar view showing another'variation in the means for-holding the housing sections in connection with the tubes.

Fig. 7 is an inner side elevation of the .annular portion of one of the housing sections showing the structure for preventing the housing sections from As shown in Figs. 1 to V4, inclusive, each housing section comprises an annular portion I having an opening in which grooves 2 are formed. The ends or the tubes 3 and 4 extend into the openings inthe respective housing members and are 4rolled or expanded into the grooves 2, thereby rigidly attaching the housing sections to the ends of -the tubes. 'I'he outer end of the opening through eachannular portion I has an inwardly 4tapered smoothly ground wall 5. The tapered ends 6 of the return bend 1 are smoothly ground and extend into the tapered portions of the openings through the housing members and the ta; pered walls on the ends .of the U-bend-seat closely against the walls 5 and form a leak-'proof joint. 'Ihe ends ofthe return bend are separated from the ends of the tubes by spaces 8 which are crossed by tubular liner members 9 extending `into enlarged portions in the ends of the tubes ,and the return bend. respectively. The inside diameter of the liners 9 is the same Vas the inside diameter ofthe tubes and the returnbend. The lner members 9 cooperate with the tubes and the eturn bend to form leak-proof joints.

Each housing member comprises a pair of outwardly extended armsvor walls IIJ having holes II near their outer ends. Each 'of the holes II has an outwardly inclined wall I2 adapted to be engaged by inclined walls I3 formed on the togglesl4. Each toggle I4 is formed --with a threaded hole through which a set screw^l5 is screwed into engagement with a shoulder I6 on the return bend 1. The set screws I are approximately in axial alinement, with the tubes 3 and 4, respectively, and function to force the ends ofthe return bend 'l intothehousing members and to hold the parts in such adjustmentv to maintainV a leak-proof joint. The toggles I4, having their inclined walls I 3 engaging the inclined walls I2 on the arms or walls Ill, prevent said arms or walls I0 from spreading when the screws I5 are tightened' and when theA device is vin service and subjected to high'pressure and high heat. To facilitate assembling the toggles I4, one end of each toggle isr provided with a rounded wall vI 1, so that when the' opposite end of the toggle is passed through the hole I I in one of the arms or walls I0, theround- .ed portion I1 on the opposite end of the toggle will permit said opposite end to move inwardly The outer ends of the portions I8 have com-` plementary transverse notches 22 cooperating to form a groove in which a plate 23 is seated. The plate 23 has holes 24 through which the keys 20 extend and the threaded ends `2l of said keys are beyond the plate 23. A nut 25 is screwed on the threaded end 2| of each key 20 and is separated from the plate 23 by a space 25, which arrangement permits limited relative longitudinal movement and adjustment oi the housing members I. The holes 224 are of greater transverse Width than the keys 20 (Fig. 2), so that it is possible for the housing members I to move toward and from each other to a limited extent, as required to obtain leak-proof joints when the parts of the return bend are assembled.

In the construction shown in Fig. 5, the an nular portion E ofthe housing member does not directly engage the tube but has a shoulder 2l! engaging a circumferential shoulder 28 on a collar 29 having internal grooves 3l) into which the end of the tube is rolled or expanded. The tapered ends t of the return bend "i ltelescope into the outer ends oi the collars and seat against smoothly ground tapered Walls 3i, corresponding to the tapered walls 5, and thereby maintain e teak-proof joint. The remaining elements of the structure shown in Fig. 5 are the same as the elementsv already described and like' reference numerals are applied thereto.

In the arrangement shown in Fig. 6, the annular portion i of the housing member has an internal flange 32 engaging against the inner end of a collar 33. The end of the tube is rolled or expanded into a groove 3d in the flange 32 and also into a groove 35 in the collar 33. The tapered ends 5 of the return bend extend into tapered openings in the outer ends of the collar 33 and seat against smoothly ground walls 36 to maintain a leak-proof joint.

The remaining features shown in Fig. 6 are the same as the features shown in Figs. 1 to 4, inclusive, and like reference numerals are applied to like parts.

A pair of spaced outwardly extended lugs 31 are formed integral with each end of the return bend 'l and provided with notches 38 in theirnlower edges. The devices used to withdraw or pull out the return bend 'I from the housing members for the purpose of opening the tubes so that the tubes may be cleaned or for other pur- DQses may be engaged with these lugs 31 and operatedto detach the return bends. Appropriate devices for use in detaching the rturn bends are shown in Figs. 8, 9 and 10. Said devices comprise a plate 39 adapted to be seated onthe ends oi the arms or walls I and having holes 40 to receive the outer ends of the set screws I5. Thus,

' the set screws I5, in addition to the functions altapered levers 44. The plate 33 may also be formed with a ange 45 at each end to constitute a seat for the outer end portion of the adjacent lever 44. These curved levers 44 are extended through the slots 43 and seated against the seats 45.. The inner ends of the levers 44 may then be struck by a hammer, or the like, and driven toward the plate 39, thereby forcibly withdrawing the ends of the return bends 'I from the socketsin which they are seated. Before the plate 39 is placed in position for use, the set screws I are screwed away from the shoulders i6 on the return bend, so that said set screws will not prevent the return bend from being partially withdrawn from the sockets in .the housing members. After the return bend has been loosened, the plate 39 and cooperating parts may be removed and the return bend 'I may be taken ofi.

My invention may be varied otherwise than in the particulars mentioned, and I do not restrict myself unessentially claim:

i. The combination with a return bend, of a housing therefor comprising a pair of sections, each being attached to one end oi one tube oi a pair of tubes, a portion on each of said sections extending toward the other Vsection and each having a groove that is disalined with the groove in the other section, a key attached to each ci' said sections and extending for sliding movements into the groove in the other section, a device attached to said keys iimiting extent of spreading movement of said sections, elements attached to said keys and cooperating with said device to limit extent of relative longitudinal movements of said sections, and means preventing said elements from clampingly engaging said device. v

2. The combination with a return bend, oi a housing therefor comprising a pair of sections, each of which is attached to one end of one tube oi a pair oi tubes, a portion on each of said sections extending toward the othery section and each of said sections/ having a groove disalined .from the groove in the other section, a key attached to each of said sections extending in the groove in the other section for longitudinal and lateral movements, and means-mounted on said keys limiting extent of said longitudinal and lateral movements.

3. The combination with a return bend, of a housing therefor comprising a pair of sections, each of which is attached to one end of a pair of tubes, a portion on each oi' said sections extending toward the other section and each of said sections having a groove disalined from the groove in the other section, a key attached to each of said sections extending in the groove in the other section for longitudinal and lateral movements, a plate between said housing sections having holes through which said keys extend, and means cooperating with said plate to limit extent of relative longitudinal and lateral movements of sid housing sections.

4. The combination with a return bend, of a housing therefor comprising a pair of sections, each of which is attached to one endoi.' a pair of tubes and each having agroove in the side thereof that is toward the other section, a key rigid with each section extending into said groove that is in the other section, a plate mounted between said sections and having holes through which said keys extend, means cooperating with said plate and said keys to limit relative movement of said sections away from each other, and means attached to said keys and cooperating with said plate to limit relative longitudinal movements of said sections.

5. The combination with a. return bend, of a housing therefor comprising a pair 01Er sections, each of which is attached to one end of a pair of tubes and'each having a groove in the side thereof that is toward the other section, a key rigid with each section extending into said groove that is in the other section, a plate mounted between said sections and having holes through' which said keys extend, meanscooperating with said plate and said keys to limit relative movement of said sections away from each other and to limit relative longitudinal movements of said sections, each of said sections having a tapered opening in its outerV end beyond the end of the attached tube and telescoping on the adjacent end of the return bend, and clamping means supported by said sections forholding said return bend tele- FREDERICK E. KEY. 

